Hi Peter, Thank you for the patch! Yet something to improve: [auto build test ERROR on hnaz-mm/master] url: https://github.com/intel-lab-lkp/linux/commits/Peter-Xu/mm-swap-Fix-lost-swap-bits-in-unuse_pte/20220420-053845 base: https://github.com/hnaz/linux-mm master config: s390-randconfig-r023-20220420 (https://download.01.org/0day-ci/archive/20220420/202204201313.QYiDBRbL-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project bac6cd5bf85669e3376610cfc4c4f9ca015e7b9b) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://github.com/intel-lab-lkp/linux/commit/355ac3eb45402f7aab25b76af029d4390af05238 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Peter-Xu/mm-swap-Fix-lost-swap-bits-in-unuse_pte/20220420-053845 git checkout 355ac3eb45402f7aab25b76af029d4390af05238 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): >> mm/swapfile.c:1824:2: error: use of undeclared identifier 'new_pte'; did you mean 'newpte'? new_pte = pte_mkold(mk_pte(page, vma->vm_page_prot)); ^~~~~~~ newpte mm/swapfile.c:1786:14: note: 'newpte' declared here pte_t *pte, newpte; ^ mm/swapfile.c:1826:26: error: use of undeclared identifier 'new_pte' pte = pte_mksoft_dirty(new_pte); ^ mm/swapfile.c:1828:23: error: use of undeclared identifier 'new_pte' pte = pte_mkuffd_wp(new_pte); ^ mm/swapfile.c:1829:36: error: use of undeclared identifier 'new_pte'; did you mean 'newpte'? set_pte_at(vma->vm_mm, addr, pte, new_pte); ^~~~~~~ newpte mm/swapfile.c:1786:14: note: 'newpte' declared here pte_t *pte, newpte; ^ 4 errors generated. vim +1824 mm/swapfile.c 1775 1776 /* 1777 * No need to decide whether this PTE shares the swap entry with others, 1778 * just let do_wp_page work it out if a write is requested later - to 1779 * force COW, vm_page_prot omits write permission from any private vma. 1780 */ 1781 static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, 1782 unsigned long addr, swp_entry_t entry, struct page *page) 1783 { 1784 struct page *swapcache; 1785 spinlock_t *ptl; 1786 pte_t *pte, newpte; 1787 int ret = 1; 1788 1789 swapcache = page; 1790 page = ksm_might_need_to_copy(page, vma, addr); 1791 if (unlikely(!page)) 1792 return -ENOMEM; 1793 1794 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 1795 if (unlikely(!pte_same_as_swp(*pte, swp_entry_to_pte(entry)))) { 1796 ret = 0; 1797 goto out; 1798 } 1799 1800 /* See do_swap_page() */ 1801 BUG_ON(!PageAnon(page) && PageMappedToDisk(page)); 1802 BUG_ON(PageAnon(page) && PageAnonExclusive(page)); 1803 1804 dec_mm_counter(vma->vm_mm, MM_SWAPENTS); 1805 inc_mm_counter(vma->vm_mm, MM_ANONPAGES); 1806 get_page(page); 1807 if (page == swapcache) { 1808 rmap_t rmap_flags = RMAP_NONE; 1809 1810 /* 1811 * See do_swap_page(): PageWriteback() would be problematic. 1812 * However, we do a wait_on_page_writeback() just before this 1813 * call and have the page locked. 1814 */ 1815 VM_BUG_ON_PAGE(PageWriteback(page), page); 1816 if (pte_swp_exclusive(*pte)) 1817 rmap_flags |= RMAP_EXCLUSIVE; 1818 1819 page_add_anon_rmap(page, vma, addr, rmap_flags); 1820 } else { /* ksm created a completely new copy */ 1821 page_add_new_anon_rmap(page, vma, addr); 1822 lru_cache_add_inactive_or_unevictable(page, vma); 1823 } > 1824 new_pte = pte_mkold(mk_pte(page, vma->vm_page_prot)); 1825 if (pte_swp_soft_dirty(*pte)) 1826 pte = pte_mksoft_dirty(new_pte); 1827 if (pte_swp_uffd_wp(*pte)) 1828 pte = pte_mkuffd_wp(new_pte); 1829 set_pte_at(vma->vm_mm, addr, pte, new_pte); 1830 swap_free(entry); 1831 out: 1832 pte_unmap_unlock(pte, ptl); 1833 if (page != swapcache) { 1834 unlock_page(page); 1835 put_page(page); 1836 } 1837 return ret; 1838 } 1839 -- 0-DAY CI Kernel Test Service https://01.org/lkp
